--- signup/includes/broadcast.inc	2009-01-08 20:57:27.000000000 +0200
+++ signup/includes/broadcast.inc	2009-01-08 21:12:28.000000000 +0200
@@ -107,10 +107,10 @@
  * @param $form_id
  * @param $form_values
  */
-function signup_broadcast_form_submit($form, &$form_state) {
+function signup_broadcast_form_submit($form, &$form_state, $addresses = array()) {
   global $user;
-  $addresses = signup_get_email_addresses($form_state['values']['nid']);
-  if (is_array($addresses)) {
+  $addresses = empty($addresses) ? signup_get_email_addresses($form_state['values']['nid']) : $addresses;
+  if (!empty($addresses)) {
     if (user_access('administer site configuration')) {
       $from = $form_state['values']['from'];
     }